In many vehicles, an air conditioning system is provided to increase comfort by means of which an interior space of a passenger compartment of the vehicle can be air conditioned by supplying suitably temperature controlled air. For this purpose, the vehicle air conditioning system has a supply apparatus to make available cold air and hot air. Cold air flows and hot air flows made available by the supply apparatus are mixed to form a corresponding flow of temperature controlled air in accordance with a predetermined desired temperature and supplied to the passenger compartment.
To increase the comfort, it is desirable for different zones of the passenger compartment to be individually temperature controlled so that, for example, occupants with different heat or cold sensitivity can respectively set a temperature pleasant for them in the zone in which they are located. To achieve this, a multi-zone supply module can be provided for a multi-zone operation, for example, in which valves are provided for each zone to be temperature controlled in order to set a strength and a temperature of the air flow for the corresponding zone. Such multi-zone supply modules are, however, very complex and/or expensive. This is in particular due to the fact that a higher pressure has to be made available to achieve a desired air flow for zones which are located at a larger distance from such a multi-zone supply module installed as a rule in the front region of the vehicle than for zones disposed more closely to the multi-zone supply module so that corresponding measures have to be taken to make the pressure available.
Another possibility to solve the problem consists of making available one supply module to make available cold air and hot air for the front region and a further supply module to make available cold air and hot air for the backseat area. The technical complexity associated with this and the cost associated with this are, however, not tolerable for most application areas.